Abstract: A food cooking and heating cabinet having a closed air convection system consisting of a variable speed blower in a air heating chamber for circulating air past a variable heating element, through a food holding oven, and back to the air heating chamber, a control for selecting a desired temperature to be maintained in the food holding oven, and means for comparing the temperature at the outlet and the inlet of the heating chamber to the selected temperature causing the air variable heating element to operate and the speed of the blower to increase when more heat is required and reduces both heat and blower speed as the need for the higher heat and air flow is no longer required, and when preset parameters are reached automatically sets the temperature to a preset temperature and holds the heated product to the predetermined temperature.

Abstract: An animal isolation cage ward has upper and lower confinement units positioned within a housing and mounted on wheels for mobility. The units are heated for animal comfort and have exhaust ports in each connecting to a plenum within the housing. An exhaust blower draws air inwardly through the units, through the exhaust port, and out through a duct for routing contaminated air outwardly. The cages are fitted with doors of transparent material which are slightly smaller than the door opening, so that a gap is maintained about the periphery of each of the doors for airflow into the unit. The size relationships are designed so that a slight negative pressure is maintained within each of the cage units for inward airflow. The housing is designed so that air from one unit does not contaminate the other unit. A high efficiency particulate matter filter can be installed in the exhaust duct.